Cardiac amyloidosis of transthyretin fibril protein (ATTR) type is an infiltrative cardiomyopathy characterised by ventricular wall thickening and diastolic heart failure. Increased access to cardiovascular magnetic resonance imaging has led to a marked increase in referrals to our centre of Caucasian patients with wild-type ATTR (senile systemic) amyloidosis and Afro-Caribbean patients with the hereditary ATTR V122I type. Both subtypes present predominantly as isolated cardiomyopathy. The differential diagnosis includes cardiac amyloid light-chain (AL) amyloidosis, which has a poorer prognosis and can be amenable to chemotherapy. We review here the clinical features of cardiac ATTR amyloidosis and describe the diagnostic tests to determine ATTR type. Correct diagnosis is ever more crucial given that several novel therapies for ATTR amyloidosis are on the near horizon.